As is well known, when a gas is compressed, its temperature increases. As a consequence, the compressed gas is not as dense as it would be at the same pressure but at a lower temperature.
In many instances, this is not of particular concern. However, there are probably an equal number of instances where the lesser density of the gas may have an undesirable effect on the performance of the system in which the gas is being used.
A common example of the latter is in internal combustion engine systems employing superchargers or turbochargers to compress the oxidant for the fuel, typically air. When a compressed oxidant, such as air, is delivered to the combustion chamber of an engine, engine output can be increased because the compressed air contains a greater quantity of oxygen and thus will support a greater fuel charge which in turn will provide more power.
However, the amount of power can be increased further if the compressed air is cooled after being compressed and before being subjected to combustion. The cooled compressed air will contain more oxygen than a hotter air charge at the same pressure. Consequently, an even greater fuel charge can be provided with the result that even greater power output may be obtained.
As a consequence, many such systems have so-called “intercoolers”, also known as “charge air coolers”. These devices are heat exchangers through which the combustion air passes after it has been compressed as by a turbocharger or a supercharger and before the combustion air is passed to the engine. In the heat exchanger, the compressed air is caused to reject heat to an appropriate coolant which itself may be air such as ambient air or a liquid coolant such as engine coolant.
In typical installations, as for example, in vehicles, the intercooler heat exchanger is stacked with other heat exchangers employed in the vehicle as, for example, radiators, condensers, oil coolers, etc. and thus adds to the volume requirements of the engine compartment in which such components are typically housed. Furthermore, because intercooler heat exchangers are cooling a gas rather than a liquid, rather sizable ducting may be required to deliver the compressed air from the location in the engine compartment whereat the intercooler heat exchanger is located from the turbocharger or supercharger and to the engine.
These volume requirements may hinder the designer of such a system from achieving a more aerodynamic shape for the vehicle which in turn will lead to decreased fuel efficiency.
The present invention is directed to overcoming one or more of the above problems.